'94 300ZX NA Shut off while driving, Wont start back up!

[Cloud123]

New stereo installed today and took it for a test drive for about 20 minutes. Got to a slow stop near a red light and the car immediately shut off. No sputters or stalling, just straight turn off.

Had the car towed and now I am trying to figure out what may be the issue. Car might have over heated? But I feel 80% that it is a electrical issue rather than mechanical.

Headlights and hazards turn on, but no power on the home position (no light ups or power to the car itself), and no clicks when I try to turn the key over. No sound at all when trying to turn it over.

Any thoughts? I took of the new stereo and nothing helped. Tried seeing if its a battery issue as well but it seems it is not as the car lights and stuff work. Maybe alternator or PTU? Thats what I have researched so far for this topic but I am wondering if it might be something more simple. Some also say it might be a theft prevention thing?

Any help is appreciated! Thanks everyone!

[nissanfreak12]

Just because the lights turn on does not mean the battery is good. Its could be possible the alt died causing the batt to die.

WHat happens when you try and turn it over? Does it crank? Click? If it tries to turn over, do the lights dim?

Have you checked the ECU for codes?

[Cloud123]

No crank or clicks at all. No dash lights either (such as check engine etc). I will have to get back to you with the ECU diagnostics tomorrow.

Would buying a new battery be beneficial to test?

EDIT: Jump starting it did not work either. Only lights that come on is the security light when the doors are open.

[nissanfreak12]

Take the battery somewhere to get charged and tested. If the battery is completely drained or has some plates fused together, jumping it from another car will do nothing.

You cant test the ECU with a dead battery. Check all the fuses to make sure all of then are good. You have 3 boxes, driver kick panel under dash, the main one by the driver headlight, and one by the battery.

[evildky]

Kinda sounds like the ignition switch.

[itsa300zx]

Remove the fuseable link cover in front of the battery. Look at the blue looped fuse link(far right side, closest to the fender), see if that is burnt out.

[Cloud123]

UPDATE:

Went to charge the battery first thing this morning and came back to the car. Tightened up the connection, checked the fuses also and wiggled them around just incase. Also wiggled around the theft relay thingie in the passenger foot-well area.

Got in the car and it turned back on! So I am assuming the battery was the main concern here as it might be very old and the people told me that it isnt holding a charge (100 to 94 with 2 starts of the vehicle). The stereo might have been pulling a lot of juice? I dont think this vehicle was ever really driven with the stereo on with lots of bass.

I will go ahead and buy a new battery. I still have a lot to do with the car but I am hoping it stays as a battery issue rather than something more complex.

Any reasons behind why it would randomly turn off like that though? Was it really a battery issue or wires disconnecting? I know its not the starter or fuses now as everything works as intended, yet I am very skeptical of putting the stereo back together even with a new battery in the car.

Any precautions I should take? Thanks for the help btw to all of you

[DCaff300ZX]

Glad this worked out, but unfortunately without confirmation of the true issue which is the best result from doing correct diagnostics and procedures, BTW and for future reference.
BTW, the online service manual is available here and for free, the best first source for tests and diagnostic procedures for us DIY guys. The second-best source is probably us!
So, my advise beyond the mentioned new battery purchase would be to suspect your electrical connections from an age, and suspect OEM original condition outlook. Nissan has always had electrical issues as their main issue in my MANY years of owning Nissans, and in this case (Z32) the battery connections (corrosion, age, not tight) re my main suspects as well as the possibility of a fuse or other connection having been compromised somehow, and re-seated during your wiggling of connections pre-update. Further advise would be a "sweep" of the engine control connections looking for green corrosion, very common and a huge issue, and cleaning/replacing any and all found.
My NA, before it began having it's old-car issues we all battle, began in the same way- wiggling and sometimes simple cleaning and tightening connections would sometimes "fix" problems until later...when the harness and connector replacements began.
Be prepared to do battle with the PTU harness, IACV unit and connections, CTS and injector harness all because of corrosion issues and poor OEM quality, as well as other things of that nature as Mother Nature has her way with your 24 year old Baby...and be sure to post up any issues you have in the future!